Burglar alarm



A. E. COYNE BURGLAR Jan, 6, 1925.

ALARM Filed Aug. 30, 1924 WITNESSES ATTORNEYS Patented Jan. 6, 192%.

UNl'iE SETES ANTHONY EDWARD COYNE, 01* NEVT YORK, N. Y.

BURGLAR, ALARM.

Application filed August 30, 1924.

To all whom it may concern.

Be it known that 1, ANTHONY E. COYNE, a citizen of the United States, and a resident of the city of New York, borough of Manhattan, in the county and State of New York, have invented a new and Improved Burglar Alarm, of which the following is afull, clear, and exact description.

This invention relates to burglar alarms and more particularly to portable devices which are designed for attachment to door knobs and the like so that, in the event that the door knob is turned, the alarm will be sounded.

A further object is to provide a device of this character which can be conveniently carried by travellers in the ordinary hand bag and can be easily attached to the inner knob in a hotel room so that, in the event any attempt is made to open the door from the outside, the mere turning of the knob will cause the alarm to sound.

A further object is to provide a device of this character which may be used not only in hotels but in ordinary dwellings or other places, which can be conveniently and easily attached, which will sound an alarm upon the turning of the knob, and which can be manufactured and sold at a reasonably low price.

With these and other objects in view, the invention consists in certain novel features of construction and combinations and arrangements of parts which will be more fully hereinafter described and pointed out in the claims.

In the accompanying drawings Figure 1 is a view in elevation of my improved device, showing the same attached to a door knob, the view illustrating in dot and dash lines the position of the device when the knob is partially turned;

Figure 2 is a view in elevation at right angles to Figure 1;

Figure 3 is a fragmentary view, partially in section, showing the interior of the bell:

Figure 4 is a View in plan, on a reduced scale, showing how m improved alarm may be positioned in a box or other receptacle so as to hold the same against possibility of accidental ringing;

Figure 5 is a view, similar to Figure 1, showing a modification.

My improved burglar alarm comprises a bell 1, a hanger 2 supporting the bell, and a clamp 3 supporting the hanger and adapt- Serial No. 735,144.

ed to be connected to a 'door knob 1. 5 represents a door provided with the ordinary latching means including door knobs at the opposite sides thereof, and while my improved clamp is adapted to be connected to the shank portion of the knob I shall refer to the knob as a whole as it is of course to be understood that the clamp may be connected to any portion of the knob or to the spindle or to any turning portion of the latch construction by a slight modification in the formation of the clamp or holding device.

The clamp 3 is preferably composed of a single strip of spring metal, the intermediate portion 6 of which is perforated to receive the upper end of the hanger 2, and the latter is screw-threaded to receive nuts 7 at opposite sides of the clamp to secure the hanger thereto. It is obvious that the exact manner of connecting the hanger and the clamp may be varied without departing from the invention.

The end portions of the strip forming the clamp 3 are curved or bowed so as to provide spring jaws 8, 8 to engage the opposite sides of the knob and securely clamp the device thereon yet permit removal as occasion may require. Part 2, which I refer to as a hanger, really constitutes a crank arm having a short shaft 9 at its lower end projecting into the bell 1 and having rotary mounting therein, as will more fully hereinafter appear.

The hell 1 constitutes a backplate 10 and a sounding member 11. This member 11 is removably connected to a central arbor 12 to which a spring 13 is secured at one end, the other end of the spring being fixed to a pin 1-1 on the backplate 10. The arbor 12 carries a gear wheel 15 meshing with a pinion 16 on a shaft 17. A star wheel 18 is fixed to the shaft 17 and engages the shorter end 19 of a clapper 20. This clapper 20 is provided at its free end with a hammer 21 to engage the inner face of the sounding member 11 of the bell.

The construction of the bell above referred to is well known and commonly in use on the market in connection with alarms of various kinds and I have purposely refrained from a detail description thereof.

As is common, the sounding member 11 of the bell is removable and when in place is turned to wind the spring. My invention resides more particularly in the control of the clappenand in order'to provide this control I give the clapper a bend, as indicated at 22, and I shape the shaft 9 of. general triangular form so that when the apex of the triangle or the somewhat rounded base of the triangle is positioned against the bent portion 22 the clapper is held with the shorter end thereof against the star wheel 18 and the mechanism is prevented from operation. When the shaft is turned slightly so as to present the sides of the triangle or recessed portions of the shaft to the clapper, the latter can be freely moved to"sou11d an alarm.

The base portion of the triangle, which, as above stated, is slightly rounded relativ'ely'wide so that it also holds the clapper against movement. This construction is desirable'as the device is to be carried from place to place or shipped, and, when the hanger 2 is swung around to the position shown in Figure 4, the rounded or widest portion of the shaft 9 is presented to the clapper and'the latter is held against movein'ent.

By providing. a rectangular box 23 such as shown in Figure 4 to receive the alarm, the extremity of clamp 3 can be located in the angle of the boX and will prevent a sufficient turning movement of the hanger andits shaft to allow the clapper to operate. In other words, when in the box, the alarm cannot he accidentally sounded.

In Figure 5 1 illustrate a slightly modified shape of the hanger. In the old style of, door keyholes 24 are provided below the knob and when a key is in such a keyhole its projecting end might interfere with the operation of a straight hanger so that I illustrate in this modification a hanger 2 having a laterally offset portion 25 sufiicient to allow a swinging movement of the hanger without engaginga projecting key.

The operation is as follows:

Assuming the clamp to be in position on a door knob and the parts indicated in the fiill line position (Figure 1). If the knob is turned from the outside by a burglar or other person, the inner knob will also turn and causethe hanger to assume an angular position as indicated in dot and dash lines in Figure .1. Thismovement of the hanger will cause the shaft 9 to turn sufficiently to might be made'in the general form of the parts described without departing from'my invention, and henceI do not'limit myself to the precise detail set forth but consider myself at liberty to make such slight changes andalterations as fairly fall within the spirit and scope of the appended claims.

I claim:

1. A device of the character described, comprising a bell, a hanger supporting'the hell, means for securing the hanger to a door knob shank, a shaft on the hanger of triangular shape in cross section permitting movement of the bell hammer when the shaft is partially turned, and also providing contact points at the apex and base of the triangular portion for engagement with the hammer and; holding the latter out of operation when the hanger is in a vertical position.

2. A. device of the character described, comprising belt, a hanger supporting the belt, means for securing the hanger "to a door knob shank. a shaft on the hanger of triangular shape in cross section permitting movement of the bell hammer when the shaft is partially turned andalso providing contact points at the apex and base of the triangular portion for engagement with the hammer and holding the latter out of operation when the hanger is in a vertical position, said hammer having a shaft contacting point whereby the hammer is held out of operation when the hangeris in its suspended or reversed position, and which contact point is movable to allow the'hammer to operate when the hanger is in an inclined position.

ANTHONY EDWARD '(lOYLE 

